Hackers on Friday targeted check-in and boarding systems provider Collins Aerospace, owned by RTX , disrupting operations at London’s Heathrow – Europe’s busiest airport, Berlin Airport and in Brussels. While the disruption eased significantly in Berlin and Heathrow on Sunday, according to airport officials and data, delays and flight cancellations were continuing. Brussels Airport said 50 of Sunday’s 257 scheduled departures had been cancelled to avoid long queues and last-minute cancellations. RTX said on Saturday it was working to fix the issue as quickly as possible, and that the disruption could be mitigated with manual check-in operations. An analysis by aviation data provider Cirium, opens new tab said delays at Heathrow were “low”, Berlin had “moderate” delays, while Brussels had “significant” delays.